themes-wordpress/rebalance/js/navigation.js

/* global rebalanceScreenReaderText */
( function( $ ) {

	var body, masthead, menuToggle, siteMenu, siteNavigation;

	function initMainNavigation( container ) {

		/**
		 * Use 3 column display in main menu
		 * - break top-level lists into three parts
		 * - add parent class to top-level menu items
		 */
		container.find('.menu, .nav-menu').columnlist( { size : 3 } );
		container.find( '.sub-menu,.children' ).parents( 'li' ).addClass( 'menu-item-has-children' );

		// Add dropdown toggle that displays child menu items.
		var dropdownToggle = $( '<button />', {
			'class': 'dropdown-toggle',
			'aria-expanded': false
		} ).append( $( '<span />', {
			'class': 'screen-reader-text',
			text: rebalanceScreenReaderText.expand
		} ) );

		container.find( '.menu-item-has-children > a' ).after( dropdownToggle );

		// Toggle buttons and submenu items with active children menu items.
		container.find( '.current-menu-ancestor > button' ).addClass( 'toggled-on' );
		container.find( '.current-menu-ancestor > .sub-menu' ).addClass( 'toggled-on' );

		// Add menu items with submenus to aria-haspopup="true".
		container.find( '.menu-item-has-children' ).attr( 'aria-haspopup', 'true' );

		container.find( '.dropdown-toggle' ).click( function( e ) {
			var _this            = $( this ),
				screenReaderSpan = _this.find( '.screen-reader-text' );

			e.preventDefault();
			_this.toggleClass( 'toggled-on' );
			_this.next( '.children, .sub-menu' ).toggleClass( 'toggled-on' );

			// jscs:disable
			_this.attr( 'aria-expanded', _this.attr( 'aria-expanded' ) === 'false' ? 'true' : 'false' );
			// jscs:enable
			screenReaderSpan.text( screenReaderSpan.text() === rebalanceScreenReaderText.expand ? rebalanceScreenReaderText.collapse : rebalanceScreenReaderText.expand );
		} );
	}
	initMainNavigation( $( '.main-navigation' ) );

	/**
	 * Re-initialize the main navigation when it is updated in the customizer
	 * - Borrowed from twentysixteen: https://goo.gl/O6msL1
	 */
	$( document ).on( 'customize-preview-menu-refreshed', function( e, params ) {
		if ( 'header' === params.wpNavMenuArgs.theme_location ) {
			initMainNavigation( params.newContainer );
		}
	});

	masthead         = $( '#masthead' );
	menuToggle       = masthead.find( '.menu-toggle' );
	siteMenu         = masthead.find( '.main-navigation' );
	siteNavigation   = masthead.find( '.main-navigation > div' );

	// Enable menuToggle.
	( function() {

		// Return early if menuToggle is missing.
		if ( ! menuToggle.length ) {
			return;
		}

		// Add an initial values for the attribute.
		menuToggle.add( siteNavigation ).attr( 'aria-expanded', 'false' );

		menuToggle.on( 'click.rebalance', function() {
			$( this ).add( siteMenu ).add( siteNavigation ).toggleClass( 'toggled-on' );

			// jscs:disable
			$( this ).add( siteMenu ).add( siteNavigation ).attr( 'aria-expanded', $( this ).add( siteNavigation ).attr( 'aria-expanded' ) === 'false' ? 'true' : 'false' );
			// jscs:enable
		} );
	} )();

	// Fix sub-menus for touch devices and better focus for hidden submenu items for accessibility.
	( function() {
		if ( ! siteNavigation.length || ! siteNavigation.children().length ) {
			return;
		}

		// Toggle `focus` class to allow submenu access on tablets.
		function toggleFocusClassTouchScreen() {
			if ( window.innerWidth >= 896 ) {
				$( document.body ).on( 'touchstart.rebalance', function( e ) {
					if ( ! $( e.target ).closest( '.main-navigation li' ).length ) {
						$( '.main-navigation li' ).removeClass( 'focus' );
					}
				} );
				siteNavigation.find( '.menu-item-has-children > a' ).on( 'touchstart.rebalance', function( e ) {
					var el = $( this ).parent( 'li' );

					if ( ! el.hasClass( 'focus' ) ) {
						e.preventDefault();
						el.toggleClass( 'focus' );
						el.siblings( '.focus' ).removeClass( 'focus' );
					}
				} );
			} else {
				siteNavigation.find( '.menu-item-has-children > a' ).unbind( 'touchstart.rebalance' );
			}
		}

		if ( 'ontouchstart' in window ) {
			$( window ).on( 'resize.rebalance', toggleFocusClassTouchScreen );
			toggleFocusClassTouchScreen();
		}

		siteNavigation.find( 'a' ).on( 'focus.rebalance blur.rebalance', function() {
			$( this ).parents( '.menu-item' ).toggleClass( 'focus' );
		} );
	} )();

	// Add the default ARIA attributes for the menu toggle and the navigations.
	function onResizeARIA() {
		if ( window.innerWidth < 896 ) {
			if ( menuToggle.hasClass( 'toggled-on' ) ) {
				menuToggle.attr( 'aria-expanded', 'true' );
				siteMenu.attr( 'aria-expanded', 'true' );
				siteNavigation.attr( 'aria-expanded', 'true' );
			} else {
				menuToggle.attr( 'aria-expanded', 'false' );
				siteMenu.attr( 'aria-expanded', 'false' );
				siteNavigation.attr( 'aria-expanded', 'false' );
			}
		} else {
			menuToggle.removeAttr( 'aria-expanded' );
			siteMenu.removeAttr( 'aria-expanded' );
			siteNavigation.removeAttr( 'aria-expanded' );
		}
	}

	$( document ).ready( function() {
		body = $( document.body );

		$( window )
			.on( 'load.rebalance', onResizeARIA )
			.on( 'resize.rebalance', onResizeARIA );
	} );

} )( jQuery );